Abstract：The new generation of power devices with wide bandgap semiconductors in dual active bridge (DAB) converters can produce higher voltage rise rates (dv/dt) on the alternating current (AC) side of the DAB converter. However, the many harmonic components in dv/dt lead to undesired high frequency oscillations between the distributed capacitance of the transformer and the inductive components of the DAB converter. This paper presents a time domain analytical equation for the high frequency oscillations of the transformer voltage in a π-type distributed parameter transformer model with three capacitances. The various factors influencing the oscillations are analyzed mathematically with the conclusions that dv/dt and the transformer capacitance are the main factors influencing the high frequency oscillations and that the oscillation amplitudes are reduced by reducing dv/dt in the converter. This paper also uses an experimental DAB prototype together with its corresponding circuit model based on LTspice to verify the theoretical analysis of the high frequency oscillations by simulations and experiments.
崔彬, 李欣阳, 薛芃, 蒋晓华. 双主动全桥变换器的高频振荡影响因素[J]. 清华大学学报（自然科学版）, 2020, 60(6): 530-536.
CUI Bin, LI Xinyang, XUE Peng, JIANG Xiaohua. Factors influencing high frequency oscillations in dual active bridge converters. Journal of Tsinghua University(Science and Technology), 2020, 60(6): 530-536.
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